合成路线1

A new synthesis for [14C]-labeled batanopride has been described: The starting material is 4-amino-2-hydroxybenzoic acid labeled with [14C] at the carboxy group (I). The methylation of (I) in the usual way gives 4-amino-2-methoxybenzoic acid methyl ester (II), which is treated with acetic anhydride to yield the corresponding acetamido derivative (III). Chlorination of (III) with Cl2 in acetic acid affords 4-acetamido-5-chloro-2-methoxybenzoic acid methyl ester (IV), which is hydrolyzed with aqueous NaOH to 4-amino-5-chloro-2-methoxybenzoic acid (V). The condensation of (V) with 2-(diethylamino)ethylamine (VI) by means of triethylamine and isobutyl chloroformate in THF gives the corresponding amide (VII), which is demethylated with sodium ethanethiolate in DMF to yield the phenolate (VIII). The condensation of (VIII) with 3-chloro-2-butanone (IX) in DMF affords batanopride free base (X), which is finally treated with HCl in acetone - water.